Expressways in South Korea were recently renumbered; originally they were numbered in order of construction. As of August 24th, 2001, they are numbered in a scheme somewhat similar to that of the Interstate Highway System in the United States:

• Arterial routes have two digit route numbers, with north-south routes having odd numbers, and east-west routes having even numbers. Primary routes have five and zero as their last digits respectively, while lesser routes have last digits other than five and zero.

• Branch routes have three digit route numbers, where the first two digits match that the route number of an arterial route.

• Belt lines have three digit route numbers where the first digit matches the respective city's postal code.

• Route number range 70-99 are reserved in the event of Korean reunification.

• The Gyeongbu Expressway kept the route 1 moniker, as it is South Korea's first and most important expressway.

• Expressway No 1
• Expressway No 10
• Expressway No 12
• Expressway No 15
• Expressway No 16
• Expressway No 25
• Expressway No 35
• Expressway No 37
• Expressway No 40
• Expressway No 45
• Expressway No 50
• Expressway No 55
• Expressway No 65
• Expressway No 66
• Expressway No 100
• Expressway No 104
• Expressway No 110
• Expressway No 120
• Expressway No 130
• Expressway No 251
• Expressway No 300
• Expressway No 451
• Expressway No 551